Dyfyniad APA

Heppner, P. P., Wampold, B. E., & Kivlighan, D. M. (1999). Research design in counseling (2nd ed.). Brooks/Cole/Wadsworth.

Dyfyniad Arddull Chicago

Heppner, P. Paul, Bruce E. Wampold, and Dennis M. Kivlighan. Research Design in Counseling. 2nd ed. Belmont, CA: Brooks/Cole/Wadsworth, 1999.

Dyfyniad MLA

Heppner, P. Paul, et al. Research Design in Counseling. 2nd ed. Brooks/Cole/Wadsworth, 1999.

Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.